1. Field of the Invention
The present invention relates generally to a system for readily sinking and floating one or more buoys, and more specifically, to a system for sinking and floating one or more buoys in a controlled manner and a sinkable buoy system for use with a modular water sports course.
2. Technical Background
Recreational and competitive water skiers and personal watercraft users typically practice and compete on water sports courses that include a plurality of buoys of varying diameters and colors that float on the surface and are arranged in a specific pattern to form a course. These buoys not only provide a path for a skier or personal watercraft to follow, but also typically include a path for a towboat to follow during a skiing pass. Skiers and personal watercraft users are typically judged on a run through the course based on time and their ability to successfully maneuver around the buoys. Most often, the buoys are configured in a slalom course, a trick course or a guide course that positions a boat and a skier for jumping. Courses may vary in buoy type, number and buoy position on the water.
There are currently several types of water sports courses in use, some of which include stationary courses, portable courses, controlled buoyancy courses and combinations thereof. Stationary courses typically include a permanent anchor or stake to maintain each individual buoy in a specific location. Buoys are typically attached to an anchor or stake using a tether made from a length of rope or cable that maintains the buoy at the proper height at the surface of the water. When an anchored buoy needs replacement, it is often necessary to access the anchor far below the surface of the water in order to attach a new tether. Stationary courses also include submerged cable systems, wherein buoys are attached to the cable system at multiple locations using ropes. Typical submerged cable systems include one or more cables that are linked together to form the length of the course and are held in place using large anchors placed about each end of the course. Cross-arms are typically attached laterally to the cable at various positions along the cable length. As tension is applied to the cable system as the anchors are pulled apart, the course is extended and proper distances between guide buoys are achieved. Cable systems are typically suspended about a meters below the surface of the water and are retrieved by entering the water or by grabbing the cable system with an anchor or hook to retrieve it.
Both individually anchored and submerged cable systems work quite well so long as the systems do not require repair and are able to remain in place without being disturbed during periods of inactivity. Since the buoys typically remain floating in both of these systems, they are exposed to damage from boats, swimmers, vandals, winter freezing and ultraviolet radiation that can cause the buoys to deteriorate over time. On crowded waterways, these particular courses may also become boating and swimming hazards. Further, a permanently installed stationary course may also become a point of contention among skiers, boaters and fishermen who all feel that they have a right to use that portion of the lake or river. As a result, many states and counties have enforced strict rules requiring individuals to remove buoys from the surface of the water when not in use or during certain hours. In this regard, skiers have attempted to overcome the disadvantages of stationary courses by removing the buoys after each use and allowing the remaining equipment to sink to the bottom. This results in extra time being spent in setting-up and tearing down a course between uses, specifically with regard to locating and accessing a submerged cable system, entering the water and attaching or removing the buoys.
Attempts have been made to overcome the disadvantages of stationary courses. In particular, portable courses have been developed that typically include collapsible or folding versions of submerged cable systems. Portable courses are typically carried in a user's boat to the ski site where the anchors, cable, cross-arms and buoys are assembled and launched into the water and tightened. Because of the need for a lighter course due to portability issues, these courses do not provide the durability or accuracy of the stationary anchored systems. Further, the greatest drawback to portable systems lies in the amount of time and labor required to install and retrieve them. Another drawback to these systems is the amount of space required to carry and store a portable system in a typical ski boat, and the space needed to store a portable course on land.
In an attempt to overcome the disadvantages described above, sinkable courses have been developed. In one particular example, U.S. Pat. No. 5,516,317 describes a system used to sink and float buoys. The system includes submarine devices comprising a cavity for holding both sand and an inflatable air bladder. Buoys are connected to the submarine devices using a length of rope. The weight of the sand inside a submarine device is enough to sink a buoy to the bottom of a lake or river when the air bladder is deflated. When the air bladder is inflated using air supplied via an air compressor or portable tank through a distributed network of tubing, enough buoyancy is created in the submarine to offset the weight of the sand, causing the buoys to float to the surface of the water. Thus, a course has been developed that is stationary in the sense that it does not have to be completely launched and retrieved from the water, but is moveable within the water by allowing the buoys to be floated and sunk as desired, thus reducing installation and set-up time and avoiding hazards and damage resulting from leaving buoys floating and unattended.
There are several disadvantages in the design of the system described in the U.S. Pat. No. 5,516,317 patent. First, the position of the submarine device in the system makes repair or replacement of an air bladder difficult due to the common housing and having to retrieve the heavy submarine from the water for repairs or maintenance. Further, the submarines in the '317 patent are positioned above the cable system to which they are attached, making it necessary to first retrieve the submarine from the water before the cable system itself can be retrieved. Another disadvantage of the current submarine design is the placement of the air bladder valve, which does not allow water that accidentally enters the bladder to drain. Further, maintenance of the air bladder portion results in the disturbance of the weight portion, and vice versa. Still further, maintaining the weight and the air bladder in a single submarine component requires that the internal cavity of the submarine remain accessible throughout the lifetime of the submarine, resulting in sealing issues and submarine material limitations that may be avoided by separating out the weight and air functions into separate components. Specifically, component expandability problems may be avoided using certain materials available as a result of separating air and weight components. Still further, general maintenance and repair of the U.S. Pat. No. 5,516,317 system is difficult and time consuming.
Accordingly, what is desired is an improved system to sink and float buoys that overcomes the disadvantages described above. What is further desired is a modular system including a guide buoys that may be raised to or lowered from the surface of the water using a distributed network of tubing to supply air from a single location using an air compressor or air pump. Still further, what is desired is a system for sinking and floating buoys that separates the weight component from the air bladder component in order to facilitate maintenance and repairs of the system and a cable to system to which it is attached. It would also be desirable to provide a water sports course that provides protection of the buoys from damage by other boaters and the environment, removes safety hazards associated with leaving buoys on crowded waterways, and allows skiers, boaters, and fisherman to use the same portion of a waterway for their own respective purposes.